Why some jihadi militants can be keen to get their retaliation in first

First, the 'analysis health warning'. Islamic militants are the prime suspects for the attempted bombings but are just that at the moment: suspects. One early possibility considered by investigators was that the bomb under Tiger Tiger was 'criminal' rather than terrorist in nature.

That said, most now believe they are indeed dealing with the work of a radical Islamic group. One key question is: are the bombers from Britain or from overseas? There is a chance that at least some of the bombers came from abroad specifically to carry out an attack, but this would seem unlikely. Almost all recent plots have involved British citizens or immigrants who have spent some time before the strike in the UK. Equally, the amateur nature of the bombs could indicate a failure to source the right materials in Britain by professionals who do not know the country very well, or it could indicate a lack of professional knowledge by self-radicalised, self-taught militants.

The fact that these were not suicide bombs is also interesting - almost all strikes directly commissioned by the 'al-Qaeda hardcore' of Osama bin Laden and Ayman al-Zawahiri involve the death of the bombers. This change is unlikely to be a deliberate tactic, but probably indicates a lack of long-term psychological preparation of the bombers who, if recent trends are anything to go by, are likely to be young, (possibly in their late teens) and to have been radicalised very rapidly.

Too much can be made of the 'Iraq link' to the style of bombing. Yes, vehicle bombs with gas cans and petrol have been used extensively in Baghdad in recent years, but car bombs are not a recent innovation. So were the attacks 'ordered' long in advance by people close to bin Laden via internet or other communications? It is hard to guess. All that we have at the moment is a threat on the internet saying: 'London shall be bombed today.' This was posted on a bona fide jihadi site, but by someone whose previous postings give no indication that he has genuine connections. Nor was the posting in the secured area on the site usually used by those who are 'players'.

Why now? It is likely that the bomb plot is in part a message to the UK saying OK, your Prime Minister has changed, so what? The militants are saying: what we are engaged in is far bigger than one tiny change in Western politics. This is about a battle between good and evil, the timescale is long, the cause is far greater than petty politics or even a single war, even those in Iraq or Afghanistan.

Why the target? Night clubs have been hit before. They represent a version of modernity, decadence and, for some, sexual opportunity that they are denied. One of the bombers of the night club in Bali in 2002 spoke about 'western whores flaunting themselves'. The supposed sexual depravity of the West, contrasted with the 'purity' of Islam, is a frequent theme in extremist Islamic writings.

A senior Moroccan minister recently told me that Islamic militancy was about 'getting your retaliation in first', even if the threat from the other was entirely imaginary. Last week's plots could well be the product of this logic pushed to the nth degree.